Effect of gamma irradiation and storage time on microbial growth and physicochemical characteristics of pumpkin (Cucurbita Moschata Duchesne ex Poiret) puree

MARÍA F. GLIEMMO; MARÍA E. LATORRE; PATRICIA NARVAIZ; CARMEN CAMPOS; LÍA N. GERSCHENSON

FOOD SCIENCE AND TECHNOLOGY INTERNATIONAL

SAGE PUBLICATIONS LTD

Lugar: London; Año: 2014 vol. 20 p. 71 - 80

1082-0132

The effect of gamma irradiation (0-2 kGy) and storage time (0-28 days) on microbial growth and physicochemical characteristics of a packed pumpkin puree was studied. For that purpose, a factorial design was applied. The puree contained potassium sorbate, glucose and vanillin and was stored at 25ºC. Gamma irradiation diminished and storage time increased microbial growth. A synergistic effect between both variables on microbial growth was observed. Storage time decreased pH and colour of purees. Sorbate content decreased with storage time and gamma irradiation. Mathematical models of microbial growth generated by the factorial design allowed estimating that a puree absorbing 1.63 kGy would have a shelf life of 4 days. In order to improve this time, some changes in the applied hurdles were assayed. These included a thermal treatment before irradiation, a reduction of irradiation dose to 0.75 kGy and a decrease in storage temperature at 20ºC. As a result, the shelf life of purees increased to 28 days.